If you set your properly calibrated known good cinema lens at a given lens marked distance e.g. 6ft exactly, and place the camera at exactly the same chosen distance from the focus target to the camera sensor plane (the little circle with a vertical line through it on the side of the camera body) and it is not in focus (check by rocking through the sharpest focus a few times), then your camera back focus (actually Focus Flange Distance FFD) needs adjusting. Ideally you use your widest focal length lens, wide open aperture as that will be most affected by an incorrect back focus (use NDs to avoid exposure clipping).
If the lens is not a cinema lens, or hasn't been checked for proper back focus then it may be the lens AND/OR the camera that needs adjusting.
Check with multiple lenses and at other distances and focal lengths. If multiple lenses show the same amount of being out of focus in the same direction, then that would tend to point to the camera being wrong. Although it's still possible all the lenses were set to an incorrect focal plane instead.
Another sign would be inability to reach or pass through focus at infinity (most lenses allow the focus ring to go beyond the printed infinity mark to allow for thermal & manufacturing variations, so the infinity mark is often not a precise point).
